Now the wondrous curve (antux) of the half-sphere, although resting on powerful foundations, collapsed1 and threw down the entire precinct of the sacred house. ...  Yet, the broad-breasted fane did not sink to the foundations, ... but the curve (kerai) of the eastern arch slipped off and a portion of the dome was mingled with the dust: part of it lay on the floor, and partÐa wonder to beholdÐhung in mid-air as if unsupported. ... [Paul goes on to describe how Justinian was roused to action; how he visited the ruins of the church and praised the skill of the architect Anthemius; how the church was rebuilt and re-consecrated.]  To the east there open the triple spaces of circles cut in half, and above, upon the upright collar of the walls, springs up the fourth part of a sphere: even so, above his triple-crested head and back does a peacock raise his many-eyed feathers. Men of the craft in their technical language call these crowning parts conches. ...  The middle one is girded by the priestly seats and steps ranged in a circle: the lowest part of them is drawn close together round a center on the ground, but as they rise, they widen out little by little until they reach the stalls of silver,2 and so in ever-increasing circles they wheel round the curved wall (kerai) that stands above them. This conch is followed by an arch resting on strong foundations, rectangular in plan and curved at the top, not in the form of a sphere, but in that of a cylinder cleft in twain.3 Two other columned conches, one on each side, extend westward like bent arms stretched out to embrace within these mansions the band of singers.4 These conches are lightened by columns speckled with purple bloom, ranged in half circle, holding aloft on golden capitals an overwhelming burden-columns which were once produced by the sheer (?)5 crags of Thebes on the Nile. Thus on either side are the bases of each arcade upheld on twin columns, and along the traces of the threefold conch skilled workmen did bend from below smaller arches cut in half,6 under whose springing the columns have set their capitals, bound with bronze, carved, overlaid with gold, driving away all fear. Upon the porphyry columns stand others from Thessaly, splendid flowers of verdant stone. Here are the fair galleries for the women, and they have the same form that may be seen below, except that they are adorned not with two columns, but with six Thessalian ones. One may wonder at the resolve of the man who upon two columns has bravely set thrice two, and has not hesitated to fix their bases over empty air. All the spaces between the Thessalian columns he has fenced with stone closures upon which the women may lean and rest their laborious elbows.
 Thus, as you direct your gaze towards the eastern arches, you behold a never-ceasing wonder. And upon all of them, above this covering of many curves, there rises, as it were, another arch borne on air,7 spreading out its swelling fold, and it rises to the top, to that high rim upon whose back is planted the base of the divine head-piece of the center of the church.8 Thus the deep-bosomed conch springs up into the air: at the summit it rises single, while underneath it rests on triple folds; and through fivefold openings pierced in its back it provides sources of light, sheathed in thin glass, through which, brilliantly gleaming, enters rosy-ankled Dawn.
 And towards the west one may see the same forms as towards the dawn, though there is a small difference. For there in the central space it is not drawn in a curved arc as it is at the eastern end, where the priests, learned in the art of sacrifice, preside on seats resplendent with an untold wealth of silver; at the west is a great, richly-wrought portal, not a single one, but divided into three at the boundary of the temple.  By the doors there stretches out a lengthy porch receiving those that enter beneath wide gates. It is as long as the wondrous church is broad; this space is called narthex by the Greeks. Here through the night there rises a melodious sound pleasing to the ears of Christ, giver of life, when the psalms of God-fearing David are sung with alternate voice by the sacred ministers. ...  Into the porch there open wide seven holy gates inviting the people to enter; one of these is on the narrow face of the narthex facing south, and another on the northern wing; the rest on their groaning pivots are opened by the warden in the west wall which marks the end of the church. Whither am I driven? What wind, as upon the sea, has carried away my roaming speech? The center of the church, the most renowned place, has been neglected. Return, my song, to behold a wonder scarcely to be believed when seen or heard.
 Next to the eastern and western circles—those circles cut in half—next to the twin Theban columns, are four sturdy piers (toichoi), bare in front, but on their sides and powerful backs they are bound by supports from opposite directions. The four of them rest on strong foundations, fixed on solid stones. In their midst the workman has mixed and poured the dust of fire-burnt stone,9 thus binding them together by the builder's art. Above them are bent arches of measureless size like the many-colored rounded bow of Iris: one turns towards the wing of Zephyr, another to Boreas, another to Notus, another rises upright towards fiery Eurus. Each arch joins its unshaken foot to that of the neighboring curve at either end, and so they are fixed together on the edge, but as each rises in the air in bending line, it slowly separates from its former fellow. Now, the space between the arches is filled with a fair construction. For where they bend away from one another according to the laws of art, and would have shown empty air, there springs up a wall in the shape of a triangle,10 sufficiently curved so as to join the arms on either side by the common yoke of a circular rim. On four sides these walls creep over and spread out, until they are united and run up on the back of the circle like a crown. The middle portion of the arches, as much as forms the curved rim, the builder's art has compacted of baked bricks, while the ends of the bows are made of construction stone.11 In the joints they have put sheets of soft lead lest the stones, pressing as they do upon one another and adding rude weight to weight, should have their backs broken; but with the lead inserted, the stone foundation is gently compressed.  A stone rim, rounded on all sides, has been fastened upon the backs [of the arches], where the base of the hemisphere comes down; there, too, are the winding curves of the last circle12 which the workmen have set like a crown upon the backs of the arches. Under this projecting adornment suspended stones have fashioned a narrow path like a fringe upon which the lamplighter may fearlessly walk round and kindle the sacred lights.
 Rising above this into the immeasurable air is a helmet rounded on all sides like a sphere and, radiant as the heavens, it bestrides the roof of the church. At its very summit art has depicted a cross, protector of the city. It is a wonder to see how [the dome], wide below, gradually grows less at the top as it rises. It does not, however, form a sharp pinnacle, but is like the firmament which rests on air. ...13  At the very navel the sign of the cross is depicted within a circle by means of minute mosaic so that the Saviour of the whole world may for ever protect the church; while at the base of the half-sphere are fashioned forty arched windows through which the rays of fair-haired Dawn are channelled.14...
 Now, towards the east and the west, you will see nothing beneath the arches: all is air. But towards the murmuring south wind and the rainless north there rises a mighty wall up to the chin of the rounded arch, and it is illuminated by twice four windows.15 This wall rests below on stone props, for, underneath it, six Haemonian columns,15a, like the fresh green of the emerald, hold up a tireless sinewy juncture (it is there that the women have their seats). These in turn are heaved upon massive heads by four columns fixed immovable on the ground, glittering jewels of Thessalian marble graced with locks of golden hair.16 They separate the middle mansion of the glorious church from the lengthy aisle (aithousa) that lies alongside. Never were such columns, high-crested, blooming like a grove with bright flowers, cut from the land of Molossis.
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